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Abstract
I studied the effects of white-tailed deer (Odocoileus virginianus) on floodplain and upland forest along the Missouri and Platte Rivers in eastern Nebraska. Analyses included the effects of deer browsing on vegetation, foliage and litter invertebrates, birds during the breeding season, and birds during migration. Sites with high deer abundances had fewer small woody plants and small trees. Hackberry trees (Celtis occidentalis ) were more common and had greater importance values at sites with high deer abundances. Both foliage arthropods and litter invertebrates varied between seasons. Few differences in foliage arthropod and litter invertebrate abundances existed between sites with high and low deer abundances. Canonical correlation analysis distinguished between habitat and bird variables associated with deer-altered and unaltered habitat. Cavity and canopy-nesting birds were more common and shrub-nesting birds were less common at sites with high deer abundances. Aerial foragers were more common at sites with high deer abundances. The majority of species tested were either unaffected or positively affected in deer-altered habitat. Some birds associated with understory, including Rose-breasted Grosbeaks (Pheuticus ludovicianus) and Brown Thrashers (Toxostoma rufum), were less common at sites with high deer abundances. House Wrens (Troglodytes aedon), American Robins (Turdus migatorius), Indigo Buntings (Passerina cyanea), and Eastern Towhees (Pipilo erythrophthalmus), responded differently to deer-altered habitat in upland forest than in floodplain forest. Predation on artificial nests was high (88%) throughout the study area but did not differ between sites with high and low deer abundances. Nest predation frequency on artificial nests was related to total vegetation volume and edge-to-area ratio. During spring and fall migration, short distance migrants and resident birds were more common on the ground and in the understory at sites with high deer abundances. Resident birds and migrants underutilized hackberries during spring and fall migration. Least Flycatchers ( Empidonax minimus) were positively associated with shrub density. The majority of bird species during migration did not differ in their use of deer-altered and unaltered habitat and were not associated with habitat variables.
